1. Field of the Invention
This invention relates to a tool mounting mechanism for a machine tool, particularly for a surface grinding machine, comprising a spindle sleeve, a tool spindle, e.g., a grinding wheel spindle, which is mounted without a backlash in said sleeve and has mutually opposite end portions protruding from said sleeve, a tool mounted on one of said end portions, a belt pulley mounted on the other of said end portions, a spindle carrier, which comprises at least two sleeve guiding means in which said sleeve is axially slidably mounted and one screw or a plurality of parallel screws (ball screws), which are connected to each other and to the sleeve by a crosspiece, is or are provided and is or are operable to axially adjust the spindle sleeve.
2. Description of the Prior Art
In known tool mounting mechanisms comprising a spindle sleeve, that spindle sleeve is provided on its outside peripheral surface with screw threads, which are in threded engagement with a nut, which is driven by a shaft for axially moving said sleeve. In accordance with German Patent Specification 894,969, an axial play between the nut and said screw threads is eliminated in that the nut consists of two parts, which are non-rotatably connected to each other and are axially movable relative to each other and axially forced toward each other by spring pressure.
Instead of the provision of such screw-threaded means for axially adjusting the spindle sleeve it is also known to axially adjust a spindle sleeve by means of a single ball or roller screw drive or by means of a plurality of parallel ball or roller screw drives, which are interconnected by a crosspiece. In that case it is essential to eliminate radial backlash.